Method of making adjustable jaw wrenches



Oct. 23, 1951 K. F. w. KEMPF METHOD OF MAKING ADJUSTABLE JAW WRENCHES 5 Sheets-Sheet 1 Filed Sept. 11, 1948 nuns ,1951 p K. F. w. KEMPF METHOD OF MAKING ADJUSTABLE JAW WRENCHES 3 Sheets-Sheet 2 Filed Sept. 11, 1948 .n 1 g. fl n. 5 d m y w iziFr,

Wizvvvze y n INN Oct. 23, 1951 K. F. w. KEMPF 2,572,492

METHOD OF MAKING ADJUSTABLE JAW WRENCHES Filed Sept. 11, 1948 s Sheets-Sheet 5 Jlfa 2 Z I Ira/12 212 702 Patented Oct. 23, 1951 METHOD OF MAKING ADJUSTABLE JAW WRENCHES Karl F. W. Kempf, Buffalo, N. Y., assignor to McKaig-Hatch Inc., Buflalo, N. Y., a corporation of New York Application September 11, 1948, Serial No. 48,815

11 Claims.

This invention relates to the method of making adjustable jaw wrenches.

Wrenches of this general type comprise a main wrench member having a head provided with a fixed jaw forged or otherwise formed integral and an adjustable member having a jaw and a shank serving as a guide or slide arm provided with a tooth-rack also forged or otherwise formed integral, said adjustable member being slidably carried by said main wrench member and adjusted by a Worm rotatably mounted in said main wrench member for coaction with said tooth-rack.

In producing blanks for this general type of wrench by means of forging methods as now practiced, the metal stock from which the blanks are formed is heated to the temperature or degree necessary to enable the forging hammer or other forging medium to reduce and reform the stock into the rough outline of that which the parts of the wrench are to finally have. Such parts, and particularly the main wrench member which includes the wrench head with its fixed jaw and the handle, are thence cold-finished by means of milling and other machine operation which are slow and costly and to a certain degree cause weakening of regions of the wrench. According to my method as herein described, such weakened regions are avoided and the wrench strengthened where most needed While retaining the streamlined appearance intended for the same. Where such milling or other mechine operations are effected against extended areas of the metal and considerable metal is removed from the blank, such as results, for instance, from broaching the head of r the main wrench member to form a finished slideway therein, only a small fraction of the number of wrench members can be prepared for further operations thereon than possible to produce within a given period of time for such further operations carried on according to my improved method of producing wrenches.

It is one of the objects of my invention to provide an adjustable-jaw wrench in which parts of the wrench which are usually subjected to greatest strain are considerably strengthened without in any manner deviating from the standard streamlined appearance of wrenches so desira'ble and so as to enable them to be more conveniently applied to otherwise inaccessible parts.

-Another object of my invention is to effect certain steps in the method of producing wrenches of this type according to improved means, as more particularly set out hereinafter, and according to which the cost of producing wrenches can be materially reduced as well as the time required to convert rough forgings or with the result that a wrench may be produced in which the jaws and the walls of the head in which the adjustable wrench member is movable will be greatly strengthened and the wrench parts prepared for further operations.

It is a further object of my invention to form the slideway in the main wrench member, which is adapted to receive the guide or slide arm of the adjustable wrench member, by a piercing or punching operation effected under a reheating of the blank or preliminarily-formed wrench part and at the same time form a strengthened jaw on said wrench part whereby, under the piercing or punching operation, the metal is caused to flow into parts where greater strength is found desirable and a jaw produced which will not readily become deformed under severe use or what is generally considered overstrains.

I wish to particularly stress the fact that machining of metal' tends to weaken the same, whereas the piercing or punching of metal while hot tends to displace the metal adjacent the opening pierced or punched, particularly when the metal of the part pierced or punched is con fined between surrounding walls provided by dies, as occurs under this method. Thus a wrench produced according to this invention can be made more desirable in appearance and rendered more strain-resisting at several points thereof when the piercing or punching operation on the metal is completed.

It is a further object of my invention to provide the slideway with rearwardly-facing flat abutments by reheating and punching the forged blank after rudimentarily formingthe slideway cylindrical under a drilling operation; the guide or slide arm of the adjustable member being correspondingly forged and machined, in cross sectional formation, so that it has flat contact faces adapted to slide in contact with the flat abutments of the slideway and thus more efiectively resist strains applied in the use of the wrench and also prevent spreading of the walls of the wrench head.

The objects of this invention as hereinbefore set out and other objects I have in mind will be more fully understood from the description to follow when taken in connection with the accompanying drawings, and the novel features of my invention will be clearly pointed out in the appended claims.

In the drawings:

Fig. 1 is a side elevation of a wrench of the general type in which my invention is utilized and according to which it is constructed, the outer end of the handle of the wrench being broken away to save space on the drawings.

Fig. 2 is a top edge view of the main wrench member in completed form.

Fig. 3 is a longitudinal section taken on line 3-3, Fig. 2.

Fig. 4' is a longitudinal section taken on line tl -l, Fig. 3.

Fig. 5 is a top edge view of the main wrench member as it appears in blank form; the dotted lines indicating beveled parts of the fixed jaw and depressed portions formed in opposite sides of the blank.

Fig. 6 is a side elevationof the forged blankf Fig. 7 is a top edge view of the blank showing a cylindrical hole drilled therethrough to be converted into a slideway having fiat rearwardlyfacing abutments.

Fig. 8 is a longitudinal section taken on line 8-8;Fig. 7; showing the cylindrical hole illustrated in Fig. 7 and showing a groove in the front-edge face of the wrench head milled or otherwise machined therein underneath the fixed jaw; the groove so formed being later converted into a throat to form what may be termed an extension of the slideway in the wrench head.

Fig. 9 is a longitudinal section taken on line 9-9. Fig. 8 looking in the direction of the arrow crossing said line.

Figs. 10. l1, l2 and 13' are'longitudinal sections through the head end of the main wrench member showing the manner of progressively punching the same to convert the cylindrical hole shown in the preceding figures into a slideway for the adjustable wrench member, said slideway being provided with flat rearwardly-facing abutments, and showing also a throat extending thro gh the head from the front end thereof to the slideway so formed, the lower end of the throat being tapered to provide a downwardly inclined rear face for the fixed jaw.

Fi 14 is a lon itudinal section throu h the head end of t e main wrench member taken on line I l-l4. Fig. 12. showing the punch in the act of for ing the slideway therein.

Fig 15 is a similar section showing the punch removed and the slideway and the throat extending forwardly therefrom, as well as the dcwnwardlv-inclined rear edge of the fixed jaw, all comp ete for assembly therewith of the adjustable jaw.

Fi 16 is a view similar to Fig. l5showing the usual transverse opening or window punched through the head of the main wrench member.

Fig 17 is a side elevation of the punch used for converting the cylindrical hole drilled in the main wrench member and the forwardly-o ening groove in the wrench head into a slideway having fiat abutments and a throat which may be said to form part of the slideway.

Fig, 18 is a front edge view of the punch.

Fig. 19 is a cross section through the punch taken on line I 9-49, Fig. 17 looking in the direction of the arrow crossing said line.

Fig. 20 is a cross section taken on line 20-40, Fig. 17, looking in the direction of the arrow crossing said line.

Fig. 21 is a cross section taken on line 2 l2l, Fig. 17.

Fig. 22 is an enlarged diagrammatic view showing the head end of the main wrench member in section confined within a suitable die or enclosure and showing the punch in association therewith intended for downward movement through the cylindrica lhole drilled in the wrench member, and also by means of arrows the flow of the metal in the jaw of said wrench member effected during the punching operation; the punch serving to enlarge the jaw underaction 4 of the punch crosswise through the wrench member while converting the cylindrical hole therein into one having flat rearwardly-facing abutments, and the groove milled or otherwise machined therein into a through slot.

Fig. 23 is. an enlarged section taken on line 2323, Fig. 22, showing the punch in the act of converting the cylindrical hole drilled into the wrench member and completing the throat previously partially formed by milling or other machine operation, and by means of arrows showing the flow of the metal taking place during the operation of punching.

In the drawings I have illustrated the major portion of a wrench embodying my invention and completed in accordance with my improved method, the free or outer portion of the handle being broken away to save space.

The wrench comprises a main wrench member 24 and an adjustable wrench member 25 having a shank 26 serving as a guide or slide arm fitted slidably in said main wrench member and an adjusting nut 2'5 rotatable within said main Wrench member and threadingly engaged with a tooth rack 28 machined in said guide or slide arm to. adjust said adjustable wrench member.

The main wrench member 24 is forged or otherwise formed from a single piece of steel or other suitable material and comprises a head 29, a fixed jaw 30 and a handle 3| usually disposed obliquely to said fixed jaw so that a longer swinging motion can be given the handle when manipulating the wrench in close quarters. It is, however, to be uncerstood that the handle 1 may be otherwise disposed with respect to the jaw 30.

The head of the wrench has a slideway 32 formed therein perpendicular to the nut-engaging or flat gripping face 33 of the jaw 31] and parallel with the front-edge face 34 of the wrench head. Extending forwardly from said slideway to said front-edge face is a slot 35 which I prefer to term a throat. The rear half of the slideway 32 is semi-cylindrical and it has its front half squared to provide a pair of flat abutments 36 for hearing thereagainst of a part of the adjustable wrench member to be hereinafter described. Said abutments lie at opposite sides of the rear opening to said throat and are commonly used by manufacturers of wrenches of this type.

The common method used to form such slideways is to first drill a cylindrical hole through the wrench member, such as shown at 3'1, Figs. 4, '7 and 9, and then by means of a broaching tool convert the semi-cylindrical front half of the drilled hole into an angular or squared half. If the throat, common to wrenches of this type, is completed before so breaching the cylindrical hole, the flat abutments will be formed by square broaching the front half of the drilled hole. If

however the semi-cylindrical front half of said hole is converted into angular or squared formation, before completin the throat, such abutments will be established only after the throat is completely formed under machine operations.

The main Wrench member is provided in rear opens into it, and into this opening the adjustin nut '2? is rotatably arranged.

The adjustable wrench member 25 comprises a jaw 39 and the guide or slide arm 26 integral therewith, said jaw extending forwardly from f the guide or slide arm and having its nut-engaging or gripping face 40 opposed to the nut-engaging or gripping face 33 of the fixed jaw 30. The guide or slide arm has a thickened rear portion 4| connected with the adjustable jaw 39 by a web 42 coextensive with said thickened portion and widened from both ends inwardly to said jaw. The jaw 39 has its rear end diverging upwardly, as at 43, substantially parallel with an inclined region 44 forming part of the front edge face 34 of the wrench head 29 so that when the adjustable jaw is moved into contact with the fixed jaw 30 of the wrench, the upwardlydiverging portion 43 of the adjustable jaw will lie in contact with the inclined region 44 of the front edge face of the wrench head.

The thickened rear portion 4| of the guide or slide arm is semi-cylindrical along its length to slidably fit into the semi-cylindrical rear portion of the slideway 32, while the front half of said thickened portion is made angular to provide squared forwardly-facing shoulders 45 which lie in contact with the flat abutments 36 of the slideway.

' The thickness of the web 42 is such as to slidably fit into the throat 35 which extends forwardly from the slideway to the front edge-face of the wrench head.

It is to be noted that the front portion of the throat is slightly widened, as best shown in Fig. 23, to provide clearance for free movement of the adjustable jaw along the wrench head of themain wrench member, a clearance of six tenthousandths of an inch at each side of the web being sufficient for the purpose. Thus, that portion of the web 42 in vertical alinement with the upwardly diverging rear face of the adjustable jaw is approximately twelve ten-thousandths of an inch thicker than the portion in rear thereof and that portion of the throat formed in the main wrench member is approximately twelve ten-thousandths of an inch wider than the rear portion thereof. This also tends to assure perfect straight-lined movement of .the adjustable wrench member on or within the main wrench member.

"The adjustin nut 2! is rotatable in the usual manner around a pintle (not shown) extending through the wnidow or lateral opening 38, the pintle being lodged in a socket 41 formed in the upper wall of said window or opening and threaded into a tapped hole 48 in the lower wall of said window or opening, as will be understood by those familiar with the art of making wrenches of this type.

The method of making and assembling the wrench parts is as follows: both the main wrench member and the adjustable wrench member are each separately forged from a single piece of high carbon steel or other suitable material and so forged, the main wrench member appears in rudimentary form as shown in Figs. 5 and 6,

and it has the head 29 formed integral with the Depressions 49 fixed jaw 30 and the handle 3|. are forged in opposite sides of the handle and depressions 53 in opposite sides of the head, the depressions 49 being for the purpose of lightening the handle while retaining the necessary rigidity for the same and for the sake of appearance and the depressions 50 to reduce the thickness of the forging to more'readily punch the window or lateral opening 38 therethrough.

The blanks forged as shown in Figs. 5 and 6 are then set up in any approved manner for drilling the cylindrical hole 31 crosswiseth'erethrough from edge to edge, as best shown in Figs. 7, 8 and 9, after which a groove 52 is milled or otherwise machined into the front edge-face 34 of the wrench head, which leaves a wall 53 between the groove 52 and the cylindrical hole 37. The milling of the blank may, without departing from my invention, be effected so as to cut through the metal from the front-edge face 34 of the head to the cylindrical hole 31 to form a slot opening into said hole, which slot may extend, if desired, to the plane of the gripping face 33 of the jaw 30, and this step in the method depends on how close the clindrical hole is drilled to the face 34 of said head.

The steps in the operation performed on the forged blank thus far considered are effected while the blanks are in a cold condition. So rudimentarily prepared, the forged blank of the main wrench member is heated to approximately 1750 F., or any temperature suitable for hot punching the same, and by means of a punch 54, shown in Figs. 17 to 21, the so rudimentarilyformed blank, whether or not it is milled through to the hole 31, is reversed from the position shown in Fig. 8 to that shown in Fig. 10 and by means of said punch, the cylindrical hole 31 is converted into the slideway 32 which is of substantially key-hole formation and has its rear half semicylindrical and its front half angular to form the flat abutments 36. At the same time the wall 53, if it exists, is punched or sheared away from between the groove 52 and the drilled hole 31, and the existence of this wall depends on whether the forged blank is milled or otherwise machined through to the cylindrical hole 31.

The initial step of converting the cylindrical hole into the slideway and of severing the wall formed between said hole and the groove 52, when such wall exists, is shown in Fig. 10, the hole being thereafter progressively converted into the slideway 32 and the wall 53 removed during the downward movement of the punch end of the tool.

From this point on I will describe the steps in the method as they occur when the blank is milled with the groove 52 so as to leave a wall 53 between the cylindrical hole 37 and said groove.

Although I have shown the punch arranged for vertical downward movement in Fig. 10, this is of no importance inasmuch as I have effected this punching operation horizontally, as well as in an inclined position. It is, of course, necessary' in effecting this punching operation that the head of the wrench be confined within suitable walls or dies and these may be of any approved construction, the confining or die walls shown in the drawing being suggestive only. Therefore, during this operation, no spreading of the walls of the wrench head can take place and as the punch progresses in its punching operation through the wrench head, it eventually removes the entire wall 53 from the head and in its final punching movement removes themetal of the head from the lower portion thereof and I particularly desire to stress the fact that the die portion of the wrench-confining medium in which the fixed jaw of the wrench head is placed, has .a curved portion 56 whose radius or radii are smaller than the radius or radii of the outer edge of the fixed jaw'as forged, as clearly shown in Figs. 10 to 12, both inclusive; thus providing a space 57 between the wall of the die and the outer edge face of the fixed jaw, which space is to be occupied by displacing metal from the wrench head in the manner to presently appear.

The tool by means of which the punching operation is effected is formed of a flat strip of metal whose thickness along its rear portion conforms to the transverse diameter of the hole 31 drilled in the wrench head.

This punch is reduced in thickness along its forward region, as at 58, and the rear edge thereof is semi-cylindrical, as at 59, to conform to the diameter which the hole 3'! is to have or which the slideway 32 is to have when finished.

The narrow portion 58 of the punch is grooved at opposite sides, as at 60, the depth of these grooves being approximately six ten-thousandths of an inch. The reduced portion 58 has its front edge beveled inwardly at its lower end, as at El,

to form a swaging edge to be used in the manner to presently appear.

The operating portion of this punch or tool is of substantially key-hole formation in cross section and is placed within a suitable power machine and the width of the rear portion thereof along its punching area, confined to the region along the reduced portion 58 thereof, equals the diameter of the cylindrical hole 31 formed in the forged blank of the main wrench member. Thus, when the lower portion of the tool is forced through the head 29 of said wrench member, substantially triangular portions of the metal, defined by the lines 62, 63 and the dotted line 64 in Fig. 23, are punched out of the head and at the same time the reduced portion 58 of the punch acts to remove the wall 53 between the cylindrical hole 3? and the groove 52 in the frontedge face of the wrench head.

As clearly shown in Figs. 10 to 13 this punch is driven through the wrench head and progressively converts the cylindrical hole 31 into the finished slideway 32 which has a semi-cylindrical rear half and a squared or angular front half, providing the fiat abutments 36. Simultaneously therewith the wall 53 between the cylindrical hole 31 and the groove 52 is removed and the groove 52 converted into the throat 35. During such action and by reason of the fluid nature of the metal caused by reheating of the blank for this punching-operation, metal in the walls of the wrench head at opposite sides of the cylindrical hole is forced forwardly and downwardly toward the inner wall surfaces of the throat, as indicated by the arrows 55 in Fig. 23; thus greatly strengthening the walls of the throat and to a degree condensing the metal therein.

In the final step of the operation of punching the wrench head to form the slideway and to complete the throat connected therewith, the swaging edge 6! of the punch acts against the inner end of the fixed jaw 39 rudimentarily formed on the blank, the lower end of the punch severing the rear portion thereof and the swaging edge forcing the hot metal remaining, forwardly and downwardly, as shown in Fig. 12, and causing the metal in the jaw to flow into the space 51 between the outer curved portion of the jaw and the wall of the die in which the jaw is clamped, as indicated by the arrows 66, Fig. 22. In this manner the fixed jaw of the wrench is widened and the metal somewhat condensed therein. A comparatively small residue or waste material is punched from the blank by the operation, as indicated by the slug 61 in said figure.

The several wrench parts are assembled in the usual manner to complete the wrench, and when theshank or slide arm 26 is entered in the slideway after filing or machining the same, and if necessary the slideway and throat, to remove fins or rough places, a perfect fit is provided and a wrench completed which has inwardly-facing abutments on one wrench part and forwardlyfacing contact faces or shoulders on the other which avoid spreading of the side walls of the wrench head when strained; thus overcoming the tendency of forcing said side Walls outwardly, as happens when the slide-arm of a wrench has convex contact faces and the front half of the slideway is made semi-cylindrical.

Punching of the slideway to desired form while the metal is heated to a semi-plastic or freely punchable state eliminates the tedious broaching or machining operations now resorted to for converting the cylindrical hole into a slideway of the shape mentioned and assures increased production of the wrench parts in which the slide- :ways are formed; thus reducing the cost of wrenches of this type and materially increasing the strength of the wrench part subjected to greatest strain.

In some of the figures of the drawings I have shown the inner surfaces of the side walls of the throat 35 straight-lined from front to rear, and when so formed a punch will be used in which the reduced front region is devoid of the grooves 60. It will be apparent, therefore, that when the grooves 60 are formed in the sides of the punch,

the inner surfaces of the side walls of the throat will have offset regions providing the advantages hereinbefore mentioned.

I wish also to state that I prefer to punch the window 38 in the forged blank by forcing a punch, suitable for the purpose, transversely through the head 27, for example such as indicated by dotted lines 68 in Fig. 16, but such window may be formed by other means, either before or after forming the slideway 35 in the head of the wrench blank.

In the process of manufacturing wrench or wrench-parts it is found good practice, generally resorted to, to forge wrench parts in large lots into rudimentarily shaped blanks under one heat so that the so forged blanks will become cool before the lot is advanced to another station in the plant for further operation. At such other station, under my method, the so forged blanks are drilled to form the hole 37 in each. This is preferably accomplished while the blanks are cold and this is followed by the milling operation before re-heating of the blanks takes place; a single operator being employed to effect each of the successive steps in the method of producing the wrench part. Such blanks thus operated upon are conveyed to another operator after an interval of possibly hours or even days or Weeks and are by him subjected to a second heat, under which conditions the blanks are punched, as for examle herein specified, either by the operator reheating such parts or by still another operator and under such conditions the cylindrical hole 3! is converted into a hole having a semi-cylindrical rear portion and an angular front portion and any metal left to form a wall, such as the wall 53, is removed so as to form what may be termed a key-hole opening in the wrench head. Any further operation required upon the so punched wrench blanks is completed under inter r'n'itteiit steps. While my method usually involves intermittent action or step operations upon the wrench blanks, it is to be understood that my improved method may be practiced under a single heating of the blanks if all steps are effected under a continuous operation, since it is possible under the first heat applied to mill or machine the head of the blank while the metal thereof is still ductile enough to permit of punching the metal by means of the tool described.

I have, in some of the claims, omitted the forging of the stock to rudimentary blank form, since the first essential step in my improved method of making a main wrench member may commence after the wrench blank is forged to rudimentary form.

Where herein reference is made to direction by using the word inner or rear or words of like connotation, it is to be construed as meaning in the direction of the handle and that the word front, outer or forward or words of like connotation, means in the direction of the jaw of the wrench member.

Having thus described my invention, what I claim is:

1. The method of forming a slideway in a main wrench member provided with a handle, a head at one end of said handle and a jaw extending from said head and forged integral therewith; which consists in heating and forging a piece of suitable metal into a blank having said handle, head and jaw rudimentarily formed, in drilling a cylindrical hole through said head in a plane at an angle to the face of said jaw, in milling into said head from the front-edge face towards or to said cylindrical hole in reheating said blank and forcing a punch through said cylindrical hole having a widened parallel sided portion rounded along its rear edge and reduced in thickness along its front portion to form angular steps on said punch at opposite sides thereof so as to punch regions of the metal outwardly from the wall of said cylindrical hole and convert said cylindrical hole into a slideway having a semi-cylindrical rear-half portion and an angular front-half portion forming flat rearwardly facing abutments and during such punching operation form a throat in said head extending from the so congell'gd slideway to the front-edge face of said 2. The method of making a wrench member from a rudimentarily-formed blank having a head, a jaw extending from said head and a handle extending therefrom in a direction different from said jaw; said method consisting in drilling a cylindrical hole through said head at an angle to the face of said jaw, in milling into said head from the front-edge face thereof towards or to said cylindrical hole, in reheating at least the head of said blank to a workable condition under punching operation, in forcing a punch having angular portions along its sides and a narrowed portion forward of said angular portions to convert said cylindrical hole into a slideway having a semi-cylindrical rear-half por tion and an angular front-half portion so as to form rearwardly facing abutments in the slideway and simultaneously therewith form a throat extending from said slideway to the front-edge face of said head should any metal be located in the path of the narrowed portion of said punch.

3. The method of making the main wrench part of an adjustablejaw wrench, which consists in heating and forging a piece of steel or other suitable metal into a rudimentarily-formed blank having a head, a jaw extending forwardly from said head and a handle extending in a rearward direction, in drilling a cylindrical hole'through said blank at an angle to the face of said jaw while said'blank is in a cold condition, in mining a groove in said head from its front-edge face toward said cylindrical hole, in reheating at least the head of said blank and punching through said blank with a punch of substanmally key-hole formation in cross section by utilizing said cylindrical hole as a guide for said punch to convert said cylindrical hole into a slideway having a semi-cylindrical rear-half portion and an angular front-half portion providing rearwardly-facing abutments, and in forming a throat in said blank under said punching operation extending from said slideway to the front-edge face of sa d head:

4. The method of making a main wrench member from a rudimentariiy formed blank having ahead, and a jaw and handle integral with said head, in drilling a cylindrical hole crosswise through said head, in machining a groove in the front-edge face of said head to provide a wall between said groove and said cylindrical hole in heating said blank to render the same easily punchable, in confining said head while heated in suitable dies, and in punching throughthe confined and heated head with a punch of keyhole formation in cross section to convert said cylindrical hole into a slideway having a semicylindrical rear-half portion and an angular front-half portion providing rearwardly-facing abutments and simultaneously therewith forming a" throat in said head extending from said converted slideway to the front-edge face of said headby punching out the wall between said groove and said cylindrical hole. 7

i 5. The method of making a main wrench member of an adjustable jaw wrench, which consistsin heating and forging a piece of steel or other suitable metal into a rudimentarily-formed blank having a, head, a handle extending rearwardlyfrom said'head and a jaw extending forwardly. therefrom, in drilling a cylindrical hole through said head at an angle to the face of said jaw, in milling or otherwise machining a, groove in thefront-edge face of said head to leave a thin wall between said groove and said cylindrical hole, in reheating said blank after forming said cylindrical hole and groove therein, in confining said head in suitable dies, in forcing a punch having a semi cylindrical rear portion conforming to one-half of said cylindrical hole and angular portions at opposite sides 'formedby reducing the thickness ofsaid punch, said pun-ch serving to reform said hole to provide flat rearwardly-facing abutmentsin said hole and to punch out the thin wall be'--- tween said'hole and said groove to form a throat extending from said converted slideway front-edge face of said head.

6.'The method of making main wrench mem bers of adjustable jaw wrenches, which consist in forming a, piece of steel or other suitable metal into a rudimentarily-formed blank having, a; head, a handle extending rearwardly from said head and a jaw extending forwardly therefrom; in forming a cylindrical hole through said head. at an angle to the face of said jaw, in heating said blankto a workable temperature approximating a condition obtainable under a tempera-1 ture of l750 F., in confining said head whilev re" heated suitable dies, and in forcing a punch of. key-hole formation in cross section through said head with its rounded portion matching one-half t t e:

1.1 of said cylindrical hole to convert the latter; into a slideway having a rearwardly facingabutment and during said. punching operation form.- ing a throat. in said head extending from said converted slideway to the front-edge faceof said head.

'll Certain steps in the method of making, main wrench members of adjustable jaw wrenches, which consists in drilling or otherwise forming a cylindrical hole crosswise through the head of a main wrench member forged or otherwise fashioned to rudimentary form, in utilizing a punch to reform said cylindrical hole into a slideway having a semi-cylindrical rear portion, an angular front portion and a throat through said head opening to the front thereof from said slideway, said punch having a semi-cylindrical rear portion conforming to the semi-cylindrical rear portion of said cylindrical hole and being reduced along its front portion to form forwardly-facing shoulders at the sides ofv said punch, the regions of said punch forming said shoulders. serving to punch out. metal fromv the wall of. said cylindrical hole so as to convert said hole into a slideway having rearwardly-facing abutments and so that the reduced front region of said punch forming said shoulders punches out any metal of said head between the transverse plane of said angular front portion and the front-edge face of said head.

8.. The method of making the main wrench members of adjustable jaw wrenches, which consists in heating and forgi g a. piece of steel or other suitable metal into a rudimentarily-formed blank having a head, a. handle extending from said head in one direction and a jaw extending therefrom in another direction, in drilling a cylindrical hole crosswise through said head, in re.- heating, at. least the head of the so forged blank into a condition of ductility for punching operation inpunching crosswise through said head:

utilizing said cylindrical, hole as a. guide to formv ber of an adjustable jaw wrench, which consists,

in heating and forging a piece of steel or other suitable metal into a rudimentarily-formed blank.

having a head. a; handle extending, in a. rearward;

direction therefrom and a jaw extending; for-- wardly therefrom, in.- drilling orotherwisev ma chining a cylindrical hole crosswise through said head, in. milling a. groove in. the. front-edge faceof; said head towards or to said cylindrical hole,. in reheating at least the head of said forged blankv to; condition the metalthereof for easy punching operation, in confining at least saidhead while reheated within the walls of a. suitablev die,,a-nd-. in then forcing a punch of key-hole formation in cross section through said. cylindrical hole to -con.- vert said hole into. a slideway having. rearwardlyfacing abutments, punch out the metal. between said; cylindrical. hole and said groove so as: tof'orma throat extending. forwardly from said converted slideway to. the front-edge. face of said head and during such punching operation. cause. metal in the. side walls of said hole. or slideway to be. forced forwardly in. opposite side wallsof! said throat and thereby strengthen the sidewalls of the head without increasing, the. thickness. of. thehead.

10. The'method of making'main wrench members of adjustable jaw wrenches, which consists in forming a head on the wrench member and a fixed jaw extending from said head, in drilling or otherwise forming a cylindrical hole in said head crosswise thereof, in milling a groove in the frontedge face of said head, in heating said head. and jaw to cause the metal thereof to flow easily under pressure, in confining the heated head within dies or other confining means in forcing a punch having forwardly facing shoulders along its sides. through said cylindrical hole while said metal is so heated so as to remove portions of the Wall of said cylindrical hole forward of its longitudinal; center and form a slideway having rearwardly-facing abutments in the front half of said hole and so that the portion of said punch forward of its shoulders forms a throat extending from said slideway to the front-edge face of said head and so that the shoulders of said punch force the metal at opposite sides of the slideway forwardly to condense the same between said punch and the confining means in which the head of said wrench member is confined.

11. The method of making main wrench members of adjustable jaw wrenches, which consists in heating and forging a piece of steel or other suitable metal into a blank having a. head, a handle extending rearwardly from said head. and a jaw extending forwardly therefrom, in drilling or otherwise forming. a cylindrical hole in said head crosswise thereof, in forming a groove in the front-edge face of said head so as to provide a wall between said cylindrical hole and said r groove in reheating at least the head and jaw of said blank to a freely punchable condition, in confiningv the head. and jaw of said blank while so heated within a die providing space between: the wall thereof and the outer-edge face of said jaw, in forcing a punch through said head and: utilizing said cylindrical hole asa guide: for said punch, the latter having awide rear portion pro-- videdwith a rounded rear edge and a narrow front portion forming. forwardly-facing shoulders and also with av swaging edge atits lower end, the forwardly-facing, shoulders? removing. metal from the wall of said cylindrical hole, the narrow front portion of said punch removing. the wall between. said cylindrical hole and said groove and the swaging edge displacing and condensing metal in the jaw of said blank, the forwardlyfacing shoulders: on. said punch converting said cylindrical hole into a. sl'ideway having a. semicylindrical rear portion and an angular front portion providing. rearwardly-facing abutments andia throat extending fromsaid slideway to the front-edge face o'f'said head, and: by means of saidswaging edge engaging the rear end: of said jaw and causing, metal; therein to be. forced forwardly. in said" jaw and fillup the space between said? jaw and the wall of the die confiing. the latter. while forming the rear end of said j'aw to desired shape.

KARL F; W.

REFERENCES GI-TED The. following references are of record in the file; of this patent:

UNITED STATES PATENTS? Number Name. Date:

I,'7.3.9;7.15: Eclcland Dec. 1 7 ,1929 2;].123840: Haist' 5-,1938 

